GENE DELIVERY INTO THE RENAL GLOMERULUS BY TRANSFER OF GENETICALLY-ENGINEERED, AUTOLOGOUS MESANGIAL CELLS

To obviate the problem of rejection in situations where cells are used as vectors for gene delivery, the feasibility of using autologous mes angial cells cultured from renal biopsy specimens was studied for the purpose of gene transfer into the glomerulus. Using the calcium-phosph ate co-precipitation method, a reporter gene which encodes bacterial b eta-galactosidase was introduced into cultured mesangial cells derived from renal biopsy tissue of rats. Stable transfectants were establish ed in the presence of a selection drug and then transferred back into the contralateral kidneys of the same animals via renal artery injecti on. Among 5 rats tested, expression of beta-galactosidase was detected in the isolated glomeruli from 4 injected kidneys. One week after cel l injection, 31 +/- 13% of the glomeruli showed positive X-gal (5-brom o-4-chloro-3-indolyl beta-D-galactopyranoside) staining, indicating ex pression of the transferred gene. The use of autologous mesangial cell s from biopsy specimens is thus realistic and would be useful to obvia te the risk of rejection in the mesangial cell vector system.